It is generally known to provide cargo bags with lifting straps or panels for engagement by the tines of a forklift truck. It is the usual practice to provide woven lifting straps or webs which are attached by sewing to the side walls of the cargo bag and the lifting straps extend upwardly above the side walls and have a lifting loop formed at their upper ends. A typical cargo bag with lifting straps is illustrated in U.S. Pat. No. 4,224,970. The lifting straps of this patent are sewn to substantially the full length of the side walls of the cargo bag. However, substantially all of the lifting stress is concentrated on the area of the side walls immediately adjacent the point at which the straps are attached thereto. This concentration of the lifting stress in the areas of the bag material closely adjacent the straps has a tendency to tear the bag material and thereby limits the weight capacity of the cargo bag, particularly during lifting operations.
In order to more uniformly distribute the lifting stress it has been proposed that cargo bags be provided with lifting panels formed by folding over the upper ends of the side wall material to form lifting loops of substantially the same width as the corresponding side wall. While this type of lifting loop is effective to more uniformly distribute the lifting stress along the area of the side walls, the wide lifting loops are difficult to thread onto the lifting tines of a forklift truck. Typical examples of cargo bags with relatively wide lifting loops formed of the side wall material are illustrated in U.S. Pat. Nos. 3,292,813; 4,136,723; and 4,191,229.